DM385 datasheet(179/281 Pages) TI

179 / 281 page

MDCLK

MDIO

(input)

DM385, DM388

www.ti.com

SPRS821D – MARCH 2013 – REVISED DECEMBER 2013

8.6.3

Management Data Input/Output (MDIO)

The Management Data Input/Output (MDIO) module continuously polls all 32 MDIO addresses in order to

enumerate all PHY devices in the system.

The MDIO module implements the 802.3 serial management interface to interrogate and control Ethernet

PHYs using a shared two-wire bus. Host software uses the MDIO module to configure the auto-

negotiation parameters of each PHY attached to the EMAC SW, retrieve the negotiation results, and

configure required parameters in the EMAC SW module for correct operation. The module is designed to

allow almost transparent operation of the MDIO interface, with very little maintenance from the core

processor. A single MDIO interface is pinned out to control the PHY configuration and status monitoring.

Multiple external PHYs can be controlled by the MDIO interface.

For more detailed information on the MDIO peripheral, see the 3PSW Ethernet Subsystem chapter in the

device-specific Technical Reference Manual.

8.6.3.1

MDIO Peripheral Register Descriptions

The MDIO peripheral registers are described in the device-specific Technical Reference Manual. Each

the peripherals are in the device memory map (see Section 2.10).

8.6.3.2

MDIO Electrical Data/Timing

Table 8-23. Timing Requirements for MDIO Input

(see Figure 8-18)

OPP100/OPP120/

Turbo/Nitro

NO.

UNIT

MIN

MAX

tc(MDCLK)

Cycle time, MDCLK

400

tw(MDCLK)

Pulse duration, MDCLK high or low

180

tsu(MDIO-MDCLKH)

Setup time, MDIO data input valid before MDCLK high

th(MDCLKH-MDIO)

Hold time, MDIO data input valid after MDCLK high

Figure 8-18. MDIO Input Timing

Table 8-24. Switching Characteristics Over Recommended Operating Conditions for MDIO Output

(see Figure 8-19)

OPP100/OPP120/

Turbo/Nitro

NO.

PARAMETER

UNIT

MIN

MAX

td(MDCLKL-MDIO)

Delay time, MDCLK low to MDIO data output valid

100

Peripheral Information and Timings

179

Submit Documentation Feedback

Product Folder Links: DM385 DM388

DM385 Datasheet(PDF) 179 Page - Texas Instruments

DM385 Datasheet(HTML) 179 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL